Add the `revng::cantFail` function which allows to wrap functions with
`std::error_code` and check their result. This is analogous to
`llvm::cantFail` for `llvm::Error`.
This commit adds the following enhancements to `TemporaryFile`:
* Adds TemporaryFile::make to allow catching the error if the temporary
file creation fails
* Fix the move assignment, as it would leak the original file until shutdown
* Fix the destructor, as it would be called even on a moved object
Giacomo Vercesi